β-Carboline–Carbohydrate hybrids: molecular design, chemical synthesis and evaluation of novel DNA photocleavers

β-Carboline present in β-carboline alkaloids from marine organisms was found, for the first time, to cleave DNA at the guanine site upon irradiation with UV light with a long wavelength without any additive, and β-carboline–carbohydrate hybrid system was effective for DNA cleavage.